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arXiv · 2011.14975

Observing UT1-UTC with VGOS

Rüdiger Haas·Eskil Varenius·Saho Matsumoto·Matthias Schartner
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Abstract

We present first results of UT1-UTC determinations using the VLBI Global Observing System (VGOS). During December 2019 through February 2020 a series of 1~hour long observing sessions were performed using the VGOS stations at Ishioka in Japan and the Onsala twin telescopes in Sweden. The data of this VGOS-B series were correlated, post-correlation processed, and analysed at the Onsala Space Observatory. The derived UT1-UTC results were compared to corresponding results from standard legacy S/X Intensive sessions (INT1/INT2), as well to the final values of the International Earth Rotation and Reference Frame Service (IERS), provided in IERS Bulletin~B. The VGOS-B series achieve 3-4 times lower formal uncertainties for the UT1-UTC results than standard legacy S/X INT series. Furthermore, the root mean square (RMS) agreement with respect to the IERS Bulletin~B is 30-40 % better for the VGOS-B results than for the INT1/INT2 results.

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Rüdiger Haas, Eskil Varenius, Saho Matsumoto, Matthias Schartner. 2020-11-30. Observing UT1-UTC with VGOS. https://doi.org/10.1186/s40623-021-01396-2

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